Alloy



" Patented June 16, 1925 UNITED STATES PATENT, OFFICE.

PIERRE GIRIN, OF PARIS, FRANCE, ASSIGNOR TO SOCIETE ANONYME DE COMMENTRY,

. FO'UBCHAMBAULT & DECAZEVILLE, 0F PARIS, FRANCE.

' ALLOY.

No Drawing.

To all whom it may concern:

Be it known that I, PIERRE GIRIN, a citizen oi the Republic of France, residing at 84 Rue de Lille, Paris, Seine, France, engineer, have invented new and useful Im provements in Alloys, which is fully set forth in the following specification.

In 'my U. S. Patent No. 1,422,096, dated July 11, 1922, is described the manufacture of an alloy which resists particularly Well the corrosive action of chemical agents and has mechanical properties superior to those of steel. v

This alloy was at first manufactured in small quantities and by small apparatus;

the necessity for manufacturing on a large scale in a metallurgical apparatus like the Martin furnace has led the applicant, in order to satisfy the conditions peculiar to this mode of manufacture, to extend the limiting percentage of carbon and of manganese originally given and to increase in certain cases the percentage of nickel from 25 to 0 per cent.

The applicant has also selected among the possible constituents which may be added, those that present the most interest and has determined the practical limits in which they should be'present to satisfy the are more extended than above conditions of manufacture.

Referring to elements the functions of which have already'been proved in metallurgical practice, namely cobalt as softener, vanadium and titanium in small doses as purifiers, tungsten and molybdenum as aiding chromium in improving the resistance to corrosion in general (temperature, superheated steam, acids) there are five constituents which are regarded as necessary for all contingencies, namely, iron, nickel, chromium, manganese and carbon.

The possible applications of these alloys was-originally supposed.

The alloy obtained according to the invention by increasing the content of carbon and manganese being ractically unattacked by strong acids, is a Emtiori unattacked by organic acids and other or anic matters, and also resists alkalies in. so ution or even in igneous fusion.

Application filed December 9, 1920. Serial No. 429,545.

The typical alloy comprises The maximum content previously indicated for the carbon and manganese are carr 1ed to '1 per cent. and 5 per cent. respectively. Manganese is an indispensable con stituent for ensuring satisfactory capacity for forging. An example of the c0mposition is: 1

Ni: 22, Cr: 12, Mn: 2.5, C: 0.3, Fe: the rest.

The content of nickel may be carried to 40 per cent. to fulfill certain conditions in respect of elasticity and 'dilatation of the alloy; for example the composition of the alloy may be Ni: 37, Or: 10, Mn: 2, C: 0.5, Fe: the rest.

Such an alloy has the mean dilatation of glass (8xl0) and a modulus of elasticity in tension ]5J-- (10x10-f to 20x10-,)v of which the tempertaure coeflicient will be very small.

Additions of other metals as accessories,

such as vanadium (from 0.2 to 1 per cent), t1tan1num (from 0*:1 to 0.5 per cent), maybe made with advantage to facilitate the man- The additions indicated are made at the cost of the content of iron.

. non-oxidizability and, res stancg to chemi- '-ca l agents are required, for example:

i 1. Metallic gauze for'making the safety sheath of miners lamps as well as the sheets which, in the chemical laboratory, are introduced between glass vessels and burner flames. These articles were hitherto rapidly destroyed, because of the facility of oxidation of metal wire (iron, nickel, copper or their alloysyused hitherto in the construction of the gauze orsheets.

Metallic wires made-from the alloys specially resisting corrosion described in the aforesaid patent and in the present specificatiom-ofi'era chemical resistance infinitely superior to that of iron and of all metals. A wire of some tenths of a mm. made of one of these alloys, whenheatedto 900 C., 1 does not show a sensible alteration for several hundred hours. At 1100 C. no change occurs for more than ten hours. The wire, flexible and very supple, lends itself well to the construction of gauze. Experiments made in the chemical laboratory have shown the perfect resistance and the unlimited durability of -metallic gauze woven with these threads and used to protect glass flasks from the flame of the burner.

2. Certain parts of firearms, such as sporting guns. Therehas been sought for many years by manufacturers of sporting ns, notably guns de luxe, an 'alloyresistmg sufficiently the oxidation provoked by the products from nitrated powders and having, moreover, the mechanical properties primarily necessary in a metal for such guns, that is to say:

High mechanical strength united with an absolute lack of brittleness (a strength insufiicient to the shock produced by the deflagration of the powder being, in this application, particularly -dangerous), and, moreover, capacity for being satisfactorily worked, notably drilled, at small diameter over a great length.

The alloys here in question respond to these various desiderata. They are not oxidiza-ble and have, on the other hand, valuable mechanical properties, namely:

Tensile strength 70 to 90 kilos in the finished state, a figure variable with the degree of hardenin" according to the mode of working (r0 ling or drawing finished at a more or less low temperature, drawing cold). I

Elongation .in the finished state, 15 to 20 per cent.

1 }Resilience (by the Guillery test) 25 to 10 1 0s.

Moreover, a very important quality, they can be worked very easily at a speed from 12-15 metres per minute with high speed steels of current manufacture.

These alloys have no need of being tem+ pered and nevertheless offer a very satisfactory resistance to wear. f

3. Cutlery de luxe, as in surgical cutting blades, flexible blades, instruments for use in surgical operations, wherea metal is required which While possessing: properties comparable with those of steel for-retaining a cutting edge, elasticity and the absence of brittleness, resists the prolonged action of corrosive materials such as antiseptics; cutlery and instruments for the culinary art. l 7 The alloys described incthe aforesaid patent and in the present specification are useful in certain industries, such as the manufacture of vegetable extracts, dyestuifs, paper pulp, the preparation of textile materials of animal or vegetable origin, in which blades are used for the disintegration of various materials in the presence of various chemical agents.

The cutting edge which can be given to 1 these alloys is not absolutely comparable with-that which is obtainable in hard tempered'steel, but it is very superior to that of bronze and other alloys having nonferrous metals as basis which are used for the same purposes.

Having thus described the nature of the same invention and the best means we know of carrying the same into practical eflect,

15%, manganese 1% to 5%, carbon 0.2%

to 1%, and iron the remainder, said alloy being heat-resistant and non-co'rrodible and having ductility and malleability adapting it for wire drawing and forging.

In testimony whereof I have signed this specification.

PIERRE GIRIN. 

